Democratic leaders gathered Monday morning to call for an independent investigation into Governor Pat McCrory's involvement in a controversy over rescinded "do not drink" orders for residents living near Duke Energy coal ash ponds.

State toxicologist Ken Rudo testified last month during a deposition as part of a lawsuit against Duke Energy, filed by environmental advocates seeking to shut down the company’s coal ash ponds.

Rudo's boss, state public health director Dr. Randall Williams, reversed earlier warnings in March that told the affected residents not to drink their water. The water is contaminated with cancer-causing hexavalent chromium at levels many times higher than Rudo had determined is safe.

"The state health director's job is to protect public health," testified Rudo, who has been the state's toxicologist for nearly 30 years. "And in this specific instance, the opposite occurred. He knowingly told people that their water was safe when we knew it wasn't."

Chromium is a metallic element that occurs naturally in the environment but can also be produced by industrial activity. Its most toxic form — hexavalent chromium or chromium-6 — is known to cause lung cancer when inhaled, and the U.S. Environmental Protection Agency says it is likely to be carcinogenic when ingested.

As part of his deposition, Rudo said hexavalent chromium would cause an increased lifetime risk of causing tumors in those who drink it, especially for pregnant women, infants and children under age of 12.

Excerpts from Rudo’s deposition claim that McCrory, a former Duke Energy employee, was involved with his administration’s attempts to challenge the advisory that Rudo and other state health experts had drafted.

On page 42 of the deposition, Rudo said he was called back to speak to McCrory. When he got there, he said McCrory wasn't there but "participated for a couple of minutes by phone.” He testified he then met with McCrory’s communications director and the director of communications at the N.C. Department of Health and Human Services.

He says there were concerns about what was being told to people in the do-not-drink advisory, which were given to neighbors in June 2015.

The governor's office disputed Rudo's claims and Tuesday evening held a press conference to say he'd lied under oath.

"We don't know why Ken Rudo lied under oath, but the governor absolutely did not take part in or request this call or meeting as he suggests," said chief of staff Thomas Stith. "The fact is that the state sent homeowners near coal ash ponds all facts and safety information about their drinking water and thanks to the McCrory administration's efforts, well owners are being hooked up to municipal water supplies at Duke Energy's expense."

Monday morning, Democratic leader Representative Larry Hall called for an independent investigation into the matter.

"Families have a right to know if their drinking water is safe," he said. "And elected officials have an obligation to put health concerns first, not profit margins and public relations for big utilities."

Hall says McCrory has "systemically worked to limit the transparency on this and other issues."

"[Rudo] has put his integrity on the line, but people continue to attack him from the shadows without stepping up to the plate," Hall said. "It's clear that something inappropriate is going on here. And the stakes are too high for people to have their clean drinking water and to have faith in their government. So we can't sweep this mess under the rug."

Friday, the Catawba Riverkeeper, Greenpeace and residents near coal ash ponds filed a public records request around the controversy.

The group said the governor's office has "absolutely no evidence backing up their claim" that Rudo lied. They called the governor's office press conference the "governor’s latest attempt to sweep his former employer’s coal ash pollution under the rug."

“The ultimate goal is to find out what happened. We have multiple stories here. We have Dr. Ken Rudo’s sworn deposition and we have people within the McCrory administration who are outright calling him a liar," Zytkow said. "So the public deserves a right to know, get to the bottom of this.”

Halls says he hopes an independent investigation will reveal the truth.

"If it turns out that the governor or his staff indeed pressured Dr. Rudo to reverse the 'Do Not Drink' orders for contaminated water then someone in that executive branch - the people who ordered it - should be held to account to the citizens of North Carolina," he said. "We need the facts and then we need to fix this mess. We need to fix it now and we need a real plan for transparency and accountability."

McCrory's campaign released a statement Monday after Hall's press conference.

"Larry Hall, Roy Cooper and their cronies have decided to politicize coal ash because they ignored the problems for decades and even fought cleanup efforts," said McCrory campaign spokesman Ricky Diaz. "Instead of politics, Governor McCrory has been focused on results: cleaning up coal ash once and for all and ensuring that homeowners near ash pits get connected to municipal water supplies at Duke Energy's expense."

Friday, Duke spokeswoman Erin Culbert told WBTV "Since the groups continue to talk about 'contaminated' wells, it’d be great if you could remind folks that even following extensive study by outside experts, we continue to see no indication that ash basins have affected neighbors’ wells."

Members of Comunidad Colectiva, an immigrant advocacy group, plans to speak out against the 287g program at the Mecklenburg County Commissioners meeting Tuesday night. 287g is a federal program that allows law enforcement officers to detain illegal immigrants arrested in Mecklenburg County.

One person is dead after a fatal car crash in Pineville Monday night. The crash occurred on NC 51 near I-485 around 10 p.m. Police say two vehicles were involved in the crash. No other injuries were reported as a result of the crash.

One person is dead after a fatal car crash in Pineville Monday night. The crash occurred on NC 51 near I-485 around 10 p.m. Police say two vehicles were involved in the crash. No other injuries were reported as a result of the crash.